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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

The phenomenon of resilience among black adolescents from divorced families in the Vaal Triangle Area / by N. Te Vaarwerk

Te Vaarwerk, Natalie January 2009 (has links)
In South Africa today many adolescents are faced with having to cope with their parents' divorce. There are many risks that occur when adolescents are faced with divorce. Of late research has suggested that parental divorce is an increasingly common phenomenon in black families, but there is no literature which focuses on what contributes to black adolescents coping resiliently with their parents' divorce. The purpose of this study was to provide answers, by means of a literature review and empirical research, to what the antecedents of resilience are among black adolescents coping resiliently with their parents divorce. This was achieved by using a qualitative phenomenological design: ten semi-structured interviews were conducted with resilient black adolescents coping well with their parents' divorce. This study makes a contribution to theory because it suggests a new resilience -promoting resource for black youth from divorced homes, namely dedicated support from friends and teachers (support that is 'always' available), not noted in previous resilience studies. This study also contributed to theory by confirming that resilience promoting processes such as community-facilitated spaces (hostel residence), extra-curricular activities at school and cultural rites encourage resilience among youth whose parents are divorced. This has not been noted in previous literature studies. The findings of this study were used to draft recommendations for Life Orientation teachers on how to encourage resilience among black South African adolescents coping with the adversities of their parents' divorce. In so doing my study made a potential contribution to practice. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.
212

Factors which contribute to resilience amongst poor, second-language learners / M.F. Cronje

Cronje, Magdalena Francina January 2008 (has links)
The focus of this empirical study was on the antecedents of resilience among poor, English second-language (ESL) adolescent learners. The reasons why some adolescents in this situation are resilient and others are not, are indicated in this study. Adolescents qualify as being resilient if they are exposed to significant threat to their development, indicating high risk to the individual, and their adaptation to the threat is successful, due to support, resources or intervention. Thirty three resilient and 32 non -resilient poor, ESL adolescent learners were selected to participate in the empirical study. My study was a mixed method study because I made use of quantitative research (a survey questionnaire completed by the 65 selected learners), and qualitative research (semi-structured interviews with two identified resilient learners and a group interview with elders who are knowledgeable about young people in this community). The conclusions of my study emphasise that dynamic interactions between individual attributes, familial support, community resources, and cultural ties empower some adolescents to overcome hardships and be resilient. My findings are supported by literature. My findings cannot be generalised, as the adolescents in my study were all black, South African youth from an impoverished community in the Vaal Triangle. This is an explorative study, and themes that were identified as contributing to resilience in my study, need to be explored in future studies. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.
213

The phenomenon of resilience among adolescents with learning difficulties in the Vaal Triangle area / by J.M. Palmer

Palmer, Jolene Maeve January 2009 (has links)
The purpose of this study was to document, by means of a literature review and empirical research, the phenomenon of resilience among adolescents with learning difficulties (LD). My study was motivated by a gap in current literature. Although there are some South African studies that explore the personal antecedents of resilience in youth with LD, there were almost no studies explaining what interpersonal antecedents might contribute to resilience. The aim of the empirical study was to investigate the phenomenon of resilience among adolescent learners coping with LD. This was done by conducting phenomenological research with ten learners who have LD and attend a school for learners with special learning needs. The findings of the study are in accordance with previous studies that suggest that resilience is encouraged by dynamic processes that are both interpersonal and intrapersonal. This study makes a contribution to theory in that it suggests that resilience among adolescent learners with LD is also encouraged by their home environment and the positive relationship with siblings that might be brought on by parents treating all their children impartially. This has not been noted in previous studies. This study also raises questions about whether inclusion of all learners in mainstream schools are beneficial to learners with LD. Because my study identified interpersonal processes (unconditional acceptance, safe spaces, championship and pedagogical expertise) that promoted resilience among those participants who took part in my study, my study contributes to what was understood about the process of resilience in learners with LD and in so doing contributes to practice in that guidelines could be drafted for Life Orientation teachers based on the findings of this study. These guidelines can enable dedicated teachers to adapt their classroom environment so that a learner with LD can benefit. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.
214

The antecedents of resilience among street children / M.J. Malindi

Malindi, Macalane Junel January 2009 (has links)
The chief focus of this study was on unearthing the antecedents of resilience in children on the street and street children in institutional care. This study was motivated by the desire to understand what made some street children function resiliently in spite of the individual, familial, environmental and wider community risk process that threaten resilience. I was alerted to the participants' resilience by the unexpected positive findings after they completed the Child and Youth Resilience Measure (CYRM). Twenty street children volunteered to take part in this study. Of the 20 participants who took part in this study, 14 were children on the street who still had contact with families and six resided at a shelter with no regular contact with their families. This was a mixed methods exploratory study in which I employed the Child and Youth resilience Measure (CYRM) to collect quantitative data from all the participants, and qualitative data via individual interviews and a focus group interview. I used the interviews to provide a deeper understanding of the antecedents of resilience identified in the CYRM. My findings from this study documented individual and environmental resilience processes that enabled the participants to function resiliently despite the harshness of streetism. Many of the resilience -promoting resources unearthed have not been linked to street children and previous studies on resilient street children have not noted all inter- and intrapersonal resources identified by the street children in my study. These resources included individual resources such as role models, assertiveness, regulating themselves socially, coping mechanisms, community - based resources such as access to education as well as cultural resources which include cultural groundedness and religion. These findings show that some street children are resilient and that they develop coping mechanisms reminiscent of hidden resilience that enable them to cope with streetism. The findings of this study have implications for practice especially asset-focused approaches to supporting street children. / Thesis (Ph.D. (Education))--North-West University, Vaal Triangle Campus, 2009.
215

Resilience among middle-born children / H. van Zyl

Van Zyl, Heleneze January 2011 (has links)
Existing literature on resilience portrays middle-born children as vulnerable. Middle-born children have to face many risks, such as a tendency towards delinquent behaviour, having poor relations with family members, being low achievers and harbouring negative feelings. Many children who face risk and who consequently are in danger of maladaptive outcomes manage to bounce back from these risks. Such children are called resilient. Research suggests that resilience among children is a common phenomenon, but no literature exists that focuses specifically on resilience among middle-born children. Because of personal experience, I as the researcher believe middle-born children can display resilience in the face of their particular risks. The purpose of this study therefore was to explore, by means of a literature study and empirical research, what the antecedents of resilience among middle-born children might be. This was done by using a concurrent triangulated mixed method design: Six resilient middle-born children completed a self-report questionnaire (RSCA) and participated in semi-structured interviews. The findings were mixed and allowed understanding of what encourages resilience in middle-born children. This study contributes to theory by identifying the resilience-promoting processes (both intra- and interpersonal) which contribute to resilience among middle-born children. This study's findings also transform the stereotypical view of middle-born children as vulnerable only. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2011
216

Environmental Health Risk Perceptions and Protective Actions: A Mixed-Method Study of New Mothers in Ontario, Canada

Laferriere, Kathryn 07 April 2014 (has links)
This thesis examines mothers’ risk perceptions and protective actions as they relate to their children’s environmental health. Children are more exposed and vulnerable than adults to environmental hazards, which have been found to be associated with numerous immediate and long-term negative health outcomes, due to physiological and behavioural factors. Despite the responsibility mothers typically bear as primary caregivers to their children, little is known about how they perceive and negotiate these risks in their day-to-day lives. To better understand mothers’ perceptions and associated protective actions across socioeconomic and geographic contexts, a mixed-method approach was employed involving a quantitative telephone survey (n=606) in Peel Region and Ottawa Public Health Units and qualitative face-to-face interviews (n=15) in Ottawa. Risk perceptions were influenced by income and perceived control, and concerns ranged from chemicals in household products to outdoor air pollution. There was a commonly reported perception that mothers should automatically become more concerned and take protective actions once they have children. When financial or other barriers prevented mothers from taking direct action to reduce risks, such as switching to safer products or changing food habits, they may have relied on emotion-focused coping techniques to reduce feelings of concern, including choosing to ignore risk information. Mothers’ information sources were examined to understand how risk information is best internalized; while the most common source of environmental health risk information was the Internet, many mothers expressed their mistrust in it and would have preferred to receive information directly from healthcare providers. This research contributes to the understanding of risk perception and protective action in a largely understudied population and the findings have practical implications for risk management and communication strategies targeting pregnant women and new mothers.
217

Identifying risk and protective factors in multi–problem poor families living in Cape Town / Hope J.

Hope, Jacqueline January 2011 (has links)
From the researcher’s personal work experience it was found that there appeared to be a cycle of poverty and welfare dependency in multi–problem poor families. This research was undertaken as a means to lay foundational work in identifying risk and protective factors in multi–problem poor families living in Cape Town. A qualitative research approach was utilised and interviews were conducted with participants that met the selection criteria. The objectives of the research were to gather data in the form of deep, descriptive narrative accounts of multi–problem families’ chronosystems and current life issues, with a focus on the life challenges and difficulties that put the family at risk. The data was collected by means of interviews utilising a semi–structured interview schedule as well as tools such as genograms, ecomaps, and life lines (see Addendum 4). Analysed data indicated themes of intergenerational risk factors that included substance abuse, domestic violence, teenage pregnancy and early school dropout. It was also found that within the current generation, absent parents was a major risk factor for children. Protective factors and variables that promoted resilience in families were also explored. It was found that religious beliefs, community support systems and personal resources were the major protective factors in these families. The research findings led to the identification of a number of early–intervention projects and programmes that could be implemented to address the identified risk factors in multi–problem poor families. These interventions include school literacy and support programmes, improved sex education in schools and community support forums. / Thesis (M.A. (MW))--North-West University, Potchefstroom Campus, 2012.
218

KARČIOJO KIEČIO (LOT. ARTEMISIA ABSINTHIUM) VANDENINIO EKSTRAKTO PROTEKCINIO POVEIKIO ĮVERTINIMAS EKSPERIMENTINIAME MODELYJE IN VIVO VEIKIANT KADMIU / The Assessment of wormwood (Artemisia Absinthium) protective activity in experimental model in vivo with orally administrated heavy metal cadmium

Pavydis, Renaldas 18 June 2014 (has links)
Pagrindinis šio tyrimo tikslas buvo įvertinti karčiojo kiečio vandeninio ekstrakto protekcinį poveikį kepenims, inkstams, širdžiai ir smegenims eksperimentiniame modelyje in vivo, veikiant kadmiu. Tyrimams atrinkta Švenčionių rajone surinkta karčiojo kiečio vaistinė augalinė žaliava, kurioje nustatyta mažiausia kadmio koncentracija (0,215±0,100 µg/g) lyginant su žaliavomis iš Vilkaviškio ir Ukmergės rajonų bei su augaline žaliava įsigyta vaistinėje. Siekiant įvertinti karčiojo kiečio protekcinį poveikį pasirinktas eksperimentinis modelis in vivo, kurį sudarė karčiojo kiečio vandeninio ekstrakto paruošimas, kontrolinės ir tiriamųjų grupių sudarymas, fiziologinių rodiklių vertinimas, organų mėginių paėmimas, mineralizavimas ir toksikologinė analizė. Tyrimui pasirinkti subrendę Wistar linijos žiurkių patinai. Kontrolinės grupės žiurkės 30 d. iš eilės buvo girdomos geriamuoju vandeniu ad libitum, Cd grupės žiurkės - kadmio chlorido vandeniniu tirpalu (2 mg/l) ad libitum, Cd+KKVE grupės žiurkės - kadmio chlorido vandeniniu tirpalu (2 mg/l) ad libitum ir karčiojo kiečio vandeniniu ekstraktu 200 mg/kg/d per os. Eutanazija atlikta 31 eksperimento dieną. Paimti kepenų, inkstų, širdies ir smegenų mėginiai mineralizuoti naudojant mineralizatorių „Multiwave 3000“. Kadmio koncentracijos nustatymas atliktas „Perkin-Elmer Zeeman 3030“ elektroterminiu atominiu absorbciniu spektrofotometru. Kadmio koncentracijos vidurkis kontrolinės grupės žiurkių kepenyse buvo 0,012±0,006 µg/g, Cd grupės –... [toliau žr. visą tekstą] / The main objective was to assess wormwood aqueous extract protective activity for rat liver, kidney, heart and brain in experimental model in vivo with orally administrated heavy metal cadmium. Wormwood plant material selected for this study was collected in Švenčioniai region. Plant material had the lowest average cadmium concentration (0.215±0.100 µg/g) compared with plant materials of Vilkaviškis and Ukmergė regions and plant material purchased from pharmacy. We established experimental animal model in vivo, with the aim to evaluate protective effects of wormwood. Experimental model consisted of wormwood aqueous extract preparation, control and experimental groups formation, physiological parameters evaluation, organ sampling, mineralization and toxicological analysis. Adult male Wistar rats were selected for the study. Control group rats were administrated with drinking water ad libitum, Cd group rats - with cadmium chloride aqueous solution (2 mg/l) ad libitum, Cd+KKVE group rats - with cadmium chloride aqueous solution (2 mg/l) ad libitum and wormwood aqueous extract 200 mg/kg/day orally for 30 consecutive days. After euthanasia on the 31st day of the experiment, liver, kidney, heart, and brain samples were mineralized using mineralizator Multiwave 3000. Cadmium concentrations were estimated with Perkin – Elmer Zeeman 3030 electrothermal atomic absorption spectrophotometer. Average cadmium concentration in control group rat liver was 0.012±0.006 µg/g, Cd group – 0.245±... [to full text]
219

Safety studies with proteolytic Clostridium botulinum in high-moisture bakery products packaged under modified atmospheres

Phillips, Daphne, 1956- January 2002 (has links)
Initial challenge studies with spores of proteolytic Clostridium botulinum types A and B (~104 spores/g) showed that while air- and gas-packaged English-style crumpets (aw 0.990) and pizza crust (aw 0.960) were toxic after 42-days storage at ambient temperature (25°C), no neurotoxin was detected in bagels (a w 0.944). Further challenge studies with similarly packaged crumpets inoculated with C. botulinum (~102 spores/g), pre- or post-baking, demonstrated that all crumpets were toxic within 4 to 6 days at 25°C and that toxigenesis preceded spoilage. Furthermore, reformulating crumpets to pH 8.3 and packaging in 100% CO2 had little effect in delaying the growth of C. botulinum compared to crumpets formulated to pH 6.5 and packaged in 60% CO2. / Subsequent studies were directed at determining the levels of additional barriers that could be used to ensure the safety of high-moisture MAP crumpets. While ethanol vapour proved to be an effective additional barrier in crumpets (100-g, [aw 0.990, pH 6.5]) challenged with ~102 spores/g of C. botulinum, spoilage preceded toxigenesis due to absorption of ethanol from the package headspace by crumpets. Modelling studies in Trypticase Peptone Glucose Yeast (TPGY) broth confirmed the anti-botulinal nature of ethanol and showed that a level of ~4% (vol/vol) could be used for complete inhibition of this pathogen, depending on the aw and pH of the growth medium. However, while ethanol vapour could be used to inhibit the growth of C. botulinum in high-moisture crumpets, its anti-botulinal efficacy was influenced by the method of crumpet leavening (yeast v chemical). / Preliminary studies were also done to assess the potential of mastic oil, a novel inhibitor, against C. botulinum. While direct and indirect application of ethanolic extracts of mastic oil inhibited the growth of C. botulinum in vivo, they failed to do so in crumpets.
220

Shelf life and microbiological safety studies on minimally processed, refrigerated "sous-vide" products

Simpson, Marian V. January 1993 (has links)
Previous results indicated that lactic acid bacteria (LAB) and Bacillus spores were the predominant spoilage microorganisms in minimally processed products after 35 days storage at 15$ sp circ$C. Furthermore, most packages were swollen due to carbon dioxide production by the LAB. The fact that spores survived mild heat treatment is of concern since it implies that other more pathogenic spores, e.g. Clostridium botulinum would also survive and may pose a public health problem in products stored at 15$ sp circ$C. As such, the influence of combination treatments (viz., mild heat processing treatment, pH, water activity, storage temperature, lactic acid bacteria) were evaluated through challenge studies with selected strains of C. botulinum type A, B, and E spores. The shelf life and safety of the products following a 13D process at 75$ sp circ$C, could be extended to $ ge$42 days by a combination of pH $ le$ 5.0 and storage at 5$ sp circ$C. Other combination treatments were also effective in controlling growth of, and toxin formation in the products by C. botulinum. For instance, botulinum toxin was not detected until day 35 in inoculated spaghetti and meat sauce products (pH 5.25 and a$ sb{w}$ 0.992) with type A and B spores and stored at 15$ sp circ$C. Shelf life extension and inhibition of toxin production was also possible through reductions in a$ sb{w}$ levels achieved by addition of 1-3% salt (w/w) to the products. Water activity levels of $ le$0.983 prevented botulinum toxin production in the minimally processed spaghetti and meat sauce product for $ ge$42 days during storage at 15$ sp circ$C. / Similar trends were observed in sous-vide rice and salmon products. Furthermore, when sodium lactate was used as the humectant to lower the a$ sb{w}$ of this product, toxin production was also delayed, but not to the same extent as achieved with NaCl. When two strains of bacteriocin-producing lactic acid bacteria were co-inoculated separately in the sous-vide rice and salmon products that had been challenged with C. botulinum type E spores, toxin formation was only slightly delayed in products with added NaCl (1%), while toxin formation was neither delayed nor prevented in similarly lactic acid bacteria-treated samples with no added NaCl. Furthermore, in most of the products in which botulinum toxin was detected, spoilage preceded toxigenesis, however, in some samples stored at 5$ sp circ$C toxigenesis preceded spoilage. Addition of $ alpha$-2-macroglobulin at a level of 2.7 ppm did not delay or prevent toxin formation in the product. Microwave heating of products at half-power or full power (800 Watts) for 5 to 10 min proved effective in inactivating all of the pre-formed toxin in toxic samples. (Abstract shortened by UMI.)

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